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                        多线程
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                            <b>0.1.</b>
                        
                        多线程
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                            <b>0.2.</b>
                        
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                            <b>0.3.</b>
                        
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                            <b>0.3.1.</b>
                        
                        创建线程的方式
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                            <b>0.3.2.</b>
                        
                        NSThread 的 Target
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                            <b>0.3.3.</b>
                        
                        线程状态
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                            <b>0.3.6.</b>
                        
                        原子属性
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                            <b>0.3.7.</b>
                        
                        线程间通讯
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                            <b>0.4.</b>
                        
                        GCD
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                            <b>0.4.1.</b>
                        
                        同步 &amp; 异步
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                            <b>0.4.2.</b>
                        
                        block
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                            <b>0.4.3.</b>
                        
                        GCD 常用代码
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                            <b>0.4.4.</b>
                        
                        串行队列
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                            <b>0.4.5.</b>
                        
                        并发队列
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                            <b>0.4.6.</b>
                        
                        主队列
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                            <b>0.4.7.</b>
                        
                        同步任务的作用
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                            <b>0.4.8.</b>
                        
                        Barrier 异步
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                            <b>0.4.9.</b>
                        
                        全局队列
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                            <b>0.4.10.</b>
                        
                        延迟操作
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                            <b>0.4.11.</b>
                        
                        一次性执行
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                            <b>0.4.12.</b>
                        
                        调度组
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                            <b>0.5.</b>
                        
                        NSOperation
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                            <b>0.5.1.</b>
                        
                        基本演练
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                            <b>0.5.2.</b>
                        
                        高级演练
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                            <b>0.5.3.</b>
                        
                        与 GCD 的对比
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                            <b>0.5.4.</b>
                        
                        自定义操作
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                            <b>0.6.</b>
                        
                        异步加载图片
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                            <b>0.6.1.</b>
                        
                        搭建界面&amp;数据准备
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                            <b>0.6.2.</b>
                        
                        同步加载图像
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                            <b>0.6.3.</b>
                        
                        异步加载图像
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                            <b>0.6.4.</b>
                        
                        占位图像
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                            <b>0.6.5.</b>
                        
                        MVC
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                            <b>0.6.6.</b>
                        
                        操作缓冲池
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                            <b>0.6.7.</b>
                        
                        图像缓冲池
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                            <b>0.6.8.</b>
                        
                        代码重构
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                            <b>0.6.9.</b>
                        
                        内存警告
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                            <b>0.6.10.</b>
                        
                        黑名单
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                            <b>0.6.11.</b>
                        
                        沙盒缓存
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                            <b>0.6.12.</b>
                        
                        小结
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                            <b>0.6.13.</b>
                        
                        SDWebImage初体验
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                            <b>0.7.</b>
                        
                        仿SDWebImage
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                            <b>0.7.1.</b>
                        
                        下载操作
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                            <b>0.7.2.</b>
                        
                        测试下载操作
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                            <b>0.7.3.</b>
                        
                        下载管理器
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                            <b>0.7.4.</b>
                        
                        自定义 UIImageView
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                            <b>0.8.</b>
                        
                        SDWebImage
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                            <b>0.8.1.</b>
                        
                        第三方框架
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                            <b>0.8.2.</b>
                        
                        位移枚举
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                            <b>0.8.3.</b>
                        
                        NSCache
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                            <b>0.8.4.</b>
                        
                        SDWebImage常见面试题
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                            <b>0.9.</b>
                        
                        runloop
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                            <b>0.10.</b>
                        
                        自动释放池
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        <a href="./" >多线程</a>
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            <div class="page-wrapper" tabindex="-1">
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                    <section class="normal" id="section-">
                    
                        <h1 id="block">block</h1>
<h2 id="%E6%A6%82%E5%BF%B5">&#x6982;&#x5FF5;</h2>
<ul>
<li>block &#x662F; C &#x8BED;&#x8A00;&#x7684;</li>
<li>&#x662F;&#x4E00;&#x79CD;&#x6570;&#x636E;&#x7C7B;&#x578B;&#xFF0C;&#x53EF;&#x4EE5;&#x5F53;&#x4F5C;&#x53C2;&#x6570;&#x4F20;&#x9012;</li>
<li>&#x662F;&#x4E00;&#x7EC4;&#x9884;&#x5148;&#x51C6;&#x5907;&#x597D;&#x7684;&#x4EE3;&#x7801;&#xFF0C;&#x5728;&#x9700;&#x8981;&#x7684;&#x65F6;&#x5019;&#x6267;&#x884C;</li>
</ul>
<h3 id="%E5%8A%A8%E7%94%BB-block-%E5%9B%9E%E9%A1%BE">&#x52A8;&#x753B; block &#x56DE;&#x987E;</h3>
<pre><code class="lang-objc"><span class="hljs-keyword">self</span><span class="hljs-variable">.demoView</span><span class="hljs-variable">.center</span> = CGPointMake(<span class="hljs-keyword">self</span><span class="hljs-variable">.view</span><span class="hljs-variable">.center</span><span class="hljs-variable">.x</span>, <span class="hljs-number">0</span>);
<span class="hljs-comment">// &#x6B64;&#x65B9;&#x6CD5;&#x4F1A;&#x7ACB;&#x5373;&#x6267;&#x884C;&#x52A8;&#x753B; block</span>
[<span class="hljs-built_in">UIView</span> animateWithDuration:<span class="hljs-number">2.0</span> delay:<span class="hljs-number">0</span> usingSpringWithDamping:<span class="hljs-number">0.3</span> initialSpringVelocity:<span class="hljs-number">10</span> options:<span class="hljs-number">0</span> animations:^{
    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;&#x52A8;&#x753B;&#x5F00;&#x59CB;&quot;</span>);
    <span class="hljs-keyword">self</span><span class="hljs-variable">.demoView</span><span class="hljs-variable">.center</span> = <span class="hljs-keyword">self</span><span class="hljs-variable">.view</span><span class="hljs-variable">.center</span>;
} completion:^(<span class="hljs-built_in">BOOL</span> finished) {
    <span class="hljs-comment">// &#x4F1A;&#x5728;&#x52A8;&#x753B;&#x7ED3;&#x675F;&#x540E;&#x6267;&#x884C;</span>
    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;&#x52A8;&#x753B;&#x5B8C;&#x6210;&quot;</span>);
}];
<span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;come here&quot;</span>);
</code></pre>
<h2 id="block-%E5%9F%BA%E6%9C%AC%E6%BC%94%E7%BB%83">block &#x57FA;&#x672C;&#x6F14;&#x7EC3;</h2>
<ul>
<li>&#x6700;&#x7B80;&#x5355;&#x7684; <code>block</code></li>
</ul>
<pre><code class="lang-objc">- (<span class="hljs-keyword">void</span>)blockDemo1 {

    <span class="hljs-comment">// &#x5B9A;&#x4E49;block</span>
    <span class="hljs-comment">// &#x7C7B;&#x578B; &#x53D8;&#x91CF;&#x540D; = &#x503C;</span>
    <span class="hljs-keyword">void</span> (^block)() = ^ {
        <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;Hello block&quot;</span>);
    };

    <span class="hljs-comment">// &#x6267;&#x884C;</span>
    block();
}
</code></pre>
<blockquote>
<p>&#x4F7F;&#x7528; <code>inlineBlock</code> &#x53EF;&#x4EE5;&#x5FEB;&#x901F;&#x5B9A;&#x4E49; <code>block</code>&#xFF0C;&#x4E0D;&#x8FC7; <code>block</code> &#x4E00;&#x5B9A;&#x8981;&#x8FC7;&#x5173;</p>
</blockquote>
<ul>
<li>&#x5F53;&#x4F5C;&#x53C2;&#x6570;&#x4F20;&#x9012;</li>
</ul>
<pre><code class="lang-objc">- (<span class="hljs-keyword">void</span>)blockDemo2 {
    <span class="hljs-keyword">void</span> (^block)() = ^ {
        <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;Hello block&quot;</span>);
    };

    [<span class="hljs-keyword">self</span> demoBlock:block];
}

<span class="hljs-comment">///  &#x6F14;&#x793A; block &#x5F53;&#x4F5C;&#x53C2;&#x6570;&#x4F20;&#x9012;</span>
- (<span class="hljs-keyword">void</span>)demoBlock:(<span class="hljs-keyword">void</span> (^)())completion {
    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;&#x5E72;&#x70B9;&#x4EC0;&#x4E48;&quot;</span>);

    completion();
}
</code></pre>
<ul>
<li>&#x4F7F;&#x7528;&#x5C40;&#x90E8;&#x53D8;&#x91CF;</li>
</ul>
<pre><code class="lang-objc">- (<span class="hljs-keyword">void</span>)blockDemo3 {
    <span class="hljs-comment">// &#x6808;&#x533A;&#x53D8;&#x91CF;</span>
    <span class="hljs-keyword">int</span> i = <span class="hljs-number">10</span>;
    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;%p&quot;</span>, &amp;i);

    <span class="hljs-keyword">void</span> (^block)() = ^ {
        <span class="hljs-comment">// &#x5B9A;&#x4E49; block &#x7684;&#x65F6;&#x5019;&#x4F1A;&#x5BF9;&#x6808;&#x533A;&#x53D8;&#x91CF;&#x8FDB;&#x884C;&#x4E00;&#x6B21; copy</span>
        <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;Hello block %d %p&quot;</span>, i, &amp;i);
    };

    [<span class="hljs-keyword">self</span> demoBlock:block];
}
</code></pre>
<blockquote>
<p>&#x5982;&#x679C; block &#x4E2D;&#x4F7F;&#x7528;&#x4E86;&#x5916;&#x90E8;&#x53D8;&#x91CF;&#xFF0C;&#x4F1A;&#x5BF9;&#x5916;&#x90E8;&#x53D8;&#x91CF;&#x505A;&#x4E00;&#x6B21; <code>copy</code></p>
</blockquote>
<ul>
<li>&#x5728; block &#x4E2D;&#x4FEE;&#x6539;&#x5916;&#x90E8;&#x53D8;&#x91CF;</li>
</ul>
<pre><code class="lang-objc">- (<span class="hljs-keyword">void</span>)blockDemo4 {
    <span class="hljs-comment">// &#x6808;&#x533A;&#x53D8;&#x91CF;</span>
    __block <span class="hljs-keyword">int</span> i = <span class="hljs-number">10</span>;
    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;%p&quot;</span>, &amp;i);

    <span class="hljs-keyword">void</span> (^block)() = ^ {
        <span class="hljs-comment">// &#x5B9A;&#x4E49; block &#x7684;&#x65F6;&#x5019;&#x4F1A;&#x5BF9;&#x6808;&#x533A;&#x53D8;&#x91CF;&#x8FDB;&#x884C;&#x4E00;&#x6B21; copy</span>
        <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;Hello block %d %p&quot;</span>, i, &amp;i);
        i = <span class="hljs-number">20</span>;
    };

    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;block &#x5B9A;&#x4E49;&#x5B8C;&#x6210; %p %d&quot;</span>, &amp;i, i);

    [<span class="hljs-keyword">self</span> demoBlock:block];

    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;===&gt;%d&quot;</span>, i);
}
</code></pre>
<blockquote>
<p>&#x5982;&#x679C;&#x8981;&#x5728; block &#x5185;&#x90E8;&#x4FEE;&#x6539;&#x6808;&#x533A;&#x53D8;&#x91CF;&#xFF0C;&#x9700;&#x8981;&#x4F7F;&#x7528; <code>__block</code> &#x4FEE;&#x9970;&#x7B26;&#xFF0C;&#x5E76;&#x4E14;&#x5B9A;&#x4E49; block &#x4E4B;&#x540E;&#xFF0C;&#x6808;&#x533A;&#x53D8;&#x91CF;&#x7684;&#x5730;&#x5740;&#x4F1A;&#x53D8;&#x5316;&#x4E3A;&#x5806;&#x533A;&#x5730;&#x5740;</p>
</blockquote>
<h3 id="block-%E7%9A%84%E5%86%85%E5%AD%98%E4%BD%8D%E7%BD%AE">block &#x7684;&#x5185;&#x5B58;&#x4F4D;&#x7F6E;</h3>
<ul>
<li>&#x5168;&#x5C40;&#x533A;&#xFF1A;&#x5982;&#x679C;block&#x4E2D;&#x6CA1;&#x6709;&#x4F7F;&#x7528;&#x4EFB;&#x4F55;&#x5168;&#x5C40;&#x53D8;&#x91CF;</li>
<li>&#x6808;&#x533A;&#xFF1A;&#x5982;&#x679C; block &#x4E2D;&#x4F7F;&#x7528;&#x4E86;&#x5916;&#x90E8;&#x53D8;&#x91CF;<ul>
<li>MRC &#x6A21;&#x5F0F;&#x53EF;&#x4EE5;&#x770B;&#x5230;</li>
<li>ARC &#x6A21;&#x5F0F;&#xFF0C;&#x7CFB;&#x7EDF;&#x4F1A;&#x81EA;&#x52A8;&#x5C06; Block &#x590D;&#x5236;&#x5230;&#x5806;&#x4E2D;</li>
</ul>
</li>
<li>&#x5806;&#x533A;&#xFF1A;&#x5C06; block &#x8BBE;&#x7F6E;&#x7ED9; copy &#x5C5E;&#x6027;</li>
</ul>
<pre><code class="lang-objc"><span class="hljs-keyword">@property</span> (<span class="hljs-keyword">nonatomic</span>, <span class="hljs-keyword">copy</span>) <span class="hljs-keyword">void</span> (^myBlock)();
</code></pre>
<pre><code class="lang-objc">- (<span class="hljs-keyword">void</span>)blockDemo5 {
    <span class="hljs-keyword">int</span> i = <span class="hljs-number">10</span>;
    <span class="hljs-keyword">void</span> (^block)() = ^ {
        <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;i --- %d&quot;</span>, i);
    };

    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;%@&quot;</span>, block);

    <span class="hljs-keyword">self</span><span class="hljs-variable">.myBlock</span> = block;
}

- (<span class="hljs-keyword">void</span>)touchesBegan:(<span class="hljs-built_in">NSSet</span> *)touches withEvent:(UIEvent *)event {

    <span class="hljs-built_in">NSLog</span>(<span class="hljs-string">@&quot;%@&quot;</span>, <span class="hljs-keyword">self</span><span class="hljs-variable">.myBlock</span>);
}
</code></pre>
<blockquote>
<p>&#x6CE8;&#x610F;&#xFF1A;&#x867D;&#x7136;&#x76EE;&#x524D; ARC &#x7F16;&#x8BD1;&#x5668;&#x5728;&#x8BBE;&#x7F6E;&#x5C5E;&#x6027;&#x65F6;&#xFF0C;&#x5DF2;&#x7ECF;&#x66FF;&#x7A0B;&#x5E8F;&#x5458;&#x590D;&#x5236;&#x4E86; block&#xFF0C;&#x4F46;&#x662F;&#x5B9A;&#x4E49; <code>block</code>&#x65F6;&#xFF0C;&#x4ECD;&#x7136;&#x5EFA;&#x8BAE;&#x4F7F;&#x7528; <code>copy</code> &#x5C5E;&#x6027;</p>
</blockquote>

                    
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